1. Field of the invention
The present invention relates to a peripheral circulation improving agent. More particularly, the present invention relates to a peripheral circulation improving agent which has improved activity on peripheral circulation and is useful as a therapeutic and/or prophylactic agent of Raynaud's disease, chronic arterial obstruction (e.g., arteriosclerosis obliterans and Buerger's disease) and the like.
2. Discussion of the Background
It has been known that 1,5-benzothiazepine derivatives such as 2-(4-lower alkylphenyl)-3-lower alkanoyloxy (or hydroxy)-5-(2-di-lower alkylaminoethyl)-8-lower alkyl-2,3-dihydro-1,5-benzothiazepin-4(5H)-one and 2-(4-lower alkylphenyl)-3-lower alkanoyloxy (or hydroxy)-5-(2-mono-lower alkylaminoethyl)-8-lower alkyl-2,3-dihydro-1,5-benzothiazepin-4(5H)-one have antihypertensive, cerebral and coronary vasodilating and/or platelet aggregation-inhibiting activities (for example, EP-A-0 154 838 and EP-A-0 158 340).
It has also been known that a pharmaceutical composition of acetylsalicylic acid and the above-mentioned benzothiazepine derivatives has excellent inhibitory effects on the platelet aggregation (EP-A-0 476 854).